title: Improvement on sample clean-up for high-performance liquid chromatographic-fluorimetric determination of diarrhetic shellfish toxins using 1-bromoacetylpyrene.
abstract: Okadaic acid (OA) and dinophysistoxin-2, two of the main diarrhetic shellfish toxins, can be determined by high-performance liquid chromatography coupled to fluorimetry as pyrenacyl esters. Toxin fluorescent derivatives were obtained after quantitative derivatization with 1-bromoacetylpyrene in acetonitrile. An efficient improvement in the silica gel clean-up procedure of the pyrenacyl derivatives is reported. The clean-up cartridge is washed with hexane-dichloromethane (1:1, v/v), dichloromethane-ethyl acetate (8:2, v/v), and finally the pyrenacyl esters were eluted with dichloromethane-methanol (9:1, v/v). We compare this procedure with other methods already described. Good results were obtained with mussels, scallops and clams. The clean-up procedure showed good robustness when checked against silica and solvents activity. Using samples of mussel hepatopancreas with an OA concentration ranging from 0 to 2 micrograms OA/g hepatopancreas, the inter-assay relative standard deviation ranged from 5.5 to 12.6%.
authors.affiliation: Departamento de Farmacología, Facultad de Veterinaria, Lugo, Spain.
authors.forename: J C
authors.initials: JC
authors.lastname: González
authors.forename: M R
authors.initials: MR
authors.lastname: Vieytes
authors.forename: J M
authors.initials: JM
authors.lastname: Vieites
authors.forename: L M
authors.initials: LM
authors.lastname: Botana
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002940:Circadian Rhythm; D003967:Diarrhea / Q000139:chemically induced; D005456:Fluorescent Dyes / Q000737:chemistry*; D005517:Foodborne Diseases / Q000209:etiology; D008387:Marine Toxins / Q000032:analysis* / Q000737:chemistry; D008974:Mollusca; D019319:Okadaic Acid / Q000032:analysis / Q000737:chemistry / Q000031:analogs & derivatives; D011714:Pyrans / Q000032:analysis / Q000737:chemistry; D011721:Pyrenes / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012758:Shellfish; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D008387:Marine Toxins; D011714:Pyrans; D011721:Pyrenes; D019319:Okadaic Acid; C051904:dinophysistoxin 1; C037706:1-bromoacetylpyrene; C076221:dinophysistoxin 2